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	<head>
		<title>three.js webgl - exporter - draco</title>
		<meta charset="utf-8">
		<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
		<link type="text/css" rel="stylesheet" href="main.css">
	</head>
	<body>
		<div id="info">
			<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> webgl - exporter - draco<br/><br/>
			<button id="exportFile">Export DRC</button>
		</div>

		<script src="js/libs/draco/draco_encoder.js"></script>

		<script type="module">

			import * as THREE from '../build/three.module.js';

			import { OrbitControls } from './jsm/controls/OrbitControls.js';
			import { DRACOExporter } from './jsm/exporters/DRACOExporter.js';

			let scene, camera, renderer, exporter, mesh;

			init();
			animate();

			function init() {

				camera = new THREE.PerspectiveCamera( 45, window.innerWidth / window.innerHeight, 1, 1000 );
				camera.position.set( 200, 100, 200 );

				scene = new THREE.Scene();
				scene.background = new THREE.Color( 0xa0a0a0 );
				scene.fog = new THREE.Fog( 0xa0a0a0, 200, 1000 );

				exporter = new DRACOExporter();

				//

				const hemiLight = new THREE.HemisphereLight( 0xffffff, 0x444444 );
				hemiLight.position.set( 0, 200, 0 );
				scene.add( hemiLight );

				const directionalLight = new THREE.DirectionalLight( 0xffffff, 0.5 );
				directionalLight.position.set( 0, 200, 100 );
				directionalLight.castShadow = true;
				directionalLight.shadow.camera.top = 180;
				directionalLight.shadow.camera.bottom = - 100;
				directionalLight.shadow.camera.left = - 120;
				directionalLight.shadow.camera.right = 120;
				scene.add( directionalLight );

				// ground

				const ground = new THREE.Mesh(
					new THREE.PlaneGeometry( 2000, 2000 ),
					new THREE.MeshPhongMaterial( { color: 0x999999, depthWrite: false } )
				);
				ground.rotation.x = - Math.PI / 2;
				ground.position.y = - 75;
				ground.receiveShadow = true;
				scene.add( ground );

				const grid = new THREE.GridHelper( 2000, 20, 0x000000, 0x000000 );
				grid.material.opacity = 0.2;
				grid.material.transparent = true;
				grid.position.y = - 75;
				scene.add( grid );

				// export mesh

				const geometry = new THREE.TorusKnotGeometry( 50, 15, 200, 30 );
				const material = new THREE.MeshPhongMaterial( { color: 0x00ff00 } );
				mesh = new THREE.Mesh( geometry, material );
				mesh.castShadow = true;
				mesh.position.y = 25;
				scene.add( mesh );

				//

				renderer = new THREE.WebGLRenderer( { antialias: true } );
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.shadowMap.enabled = true;
				document.body.appendChild( renderer.domElement );

				//

				const controls = new OrbitControls( camera, renderer.domElement );
				controls.target.set( 0, 25, 0 );
				controls.update();

				//

				window.addEventListener( 'resize', onWindowResize );

				const exportButton = document.getElementById( 'exportFile' );
				exportButton.addEventListener( 'click', exportFile );

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

			}

			function animate() {

				requestAnimationFrame( animate );
				renderer.render( scene, camera );

			}

			function exportFile() {

				const result = exporter.parse( mesh );
				saveArrayBuffer( result, 'file.drc' );

			}

			const link = document.createElement( 'a' );
			link.style.display = 'none';
			document.body.appendChild( link );

			function save( blob, filename ) {

				link.href = URL.createObjectURL( blob );
				link.download = filename;
				link.click();

			}

			function saveArrayBuffer( buffer, filename ) {

				save( new Blob( [ buffer ], { type: 'application/octet-stream' } ), filename );

			}

		</script>

	</body>
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